In a well-known method of polishing a vehicle body, there is provided a portal traveling frame which is designed so as to reciprotatingly move on guide rails, the portal traveling frame being provided thereon with washing means and drying means. In such arrangement, the portal traveling frame moves in straddling a vehicle body to be polished, meanwhile the washing means and drying means accomplishes washing and drying of the vehicle body. However, in such a customary method, polishing of the vehicle body can not be made, and lustrous gloss can not be made on the vehicle body after cleaning
Hence, an apparatus wherein a polishing device is provided on the portal traveling frame has been proposed, as disclosed, for example, in Japanese Patent Publication No. 6349/1969. But in this apparatus, there was such defects that the construction is complex and of large type as a whole, and further it is high in cost and easy to break down, and inspection and adjustment are troublesome, etc., since a brush for applying wax, a brush for polishing and a brush for brush-cleaning were provided each independently.